SECOND EDITION (first ed. 1582) of Maestlin's "Epitome Astronomiae" bound with the THIRD EDITION (first ed. 1550) of Peucer's "De Dimensione Terrae". Bound in contemporary stiff vellum, ruled in blind. Internally, these are excellent copies with a very light marginal damp-stain to the margin of a few signatures and a couple of browned leaves. Both works are illustrated with diagrams and small woodcut illustrations. Leaf E1 of the Maestlin has working volvelles.

Despite the fact that six editions were published between 1582 and 1624, copies of Mästlin's text are very rare. "Copies of any edition are rare in the U.S."(Gingerich, "Rara Astronomica"(1979) no. 34)

1. Maestlin's "Epitome Astronomiae":

A fine copy of the 2nd edition of Michael Mästlin's university textbook of astronomy, printed in the year that Kepler arrived at Tübingen University. While Mästlin accepted the Copernican view of the universe, in his textbook he adhered to the Ptolemaic model, since the book was intended for general students. Nevertheless, "Maestlin regularly discussed Copernicus in his classes, and there the young Johannes Kepler first learned of Copernican astronomy." (Gingerich, Five Centuries of Astronomical Textbooks) Mästlin's heavily-annotated copy of Copernicus' "De Revolutionibus" is preserved at Schaffhousen, Switzerland.

"Of all the initial factors involved in Kepler's decision to become an advocate of the Copernican system, there is no doubt among historians that a paramount weight must be assigned to the role of his teacher of astronomy at the University of Tübingen, Michael Mästlin. There are no skeptics here simply because Kepler tells us, with typical candor, that it was Mästlin who first acquainted him with the difficulties inherent in the usual opinion of the world and that, subsequently, he was stimulated to pursue and defend the views of Copernicus on mathematical and 'physical or, if you prefer, metaphysical' grounds."(Westman, Kepler, Mästlin, and the Copernican Hypothesis)

In 1595-6, Mästlin would prepare Kepler's "Mysterium Cosmographicum" for the press; to this important work he added an important appendix on Copernican planetary theory. "It is evident that after Kepler had left the Academy at Tübingen, Maestlin continued to direct his astronomical studies, providing him with advice, corrections, and in one letter, a full and much needed exposition of Copernican theory" (Grafton)

As Charlotte Methuen has shown, while Mästlin's teaching of Copernicus met with criticism from his colleagues at Tübingen, it was not pressure of this sort that kept Mästlin from expounding Copernican cosmology in his textbook. In fact, a poem, prefixed to this and subsequent editions, proclaims Mästlin a teacher of the ideas of Copernicus. Rather, it was the fact that the "Epitome" was intended as an introduction to non-specialist students at the university. Mästlin does mention Copernicus, but only in reference to "Copernicus' observations of the sun and his calculations of planetary distances; the heliocentric hypothesis is scarcely mentioned and is certainly never discussed. However, while he describes only the Ptolemaic hypothesis, Mästlin does comment that the assertion that the earth is stationary in the middle of the universe is 'the usual understanding', indicating that other positions are possible."(Methuen)

2. Gaspar Peucer's "De Dimensione Terrae"

The German mathematician Gaspar Peucer, a student of Philip Melanchthon, wrote his "De Dimensione Terrae" as a geographic addition to Melanchthon's "Physics". He was mainly concerned with the mathematical aspects of universal geography but added a descriptive geography of the Holy Land. He references Copernicus' trigonometric tables.